Condenser



Dec. 3, 1929. MORRIS ET AL 1,738,194

CONDENSER Filed March 21, 1927 4 Sheets-Sheet 1 Dec. 3, 1929. R. B. MORRIS El AL CONDENSER Filed March 21, 1927 4 Sheets-8heet 2 19 anon Wow W26, may;

Dec. 3, 1929. R. B. MORRIS ET AL 1,738,194

CONDENSER Filed March 21, 1927 4 Sheets-Sheet 3 vwemtow Dec. 3, 1929. R. B. MORRIS ET AL CONDENSER Filed March 21, 1927 4 Sheets-Sheet 4 Patented Dec. 3, 1929 UETE STATES PTE OF SOUTH ORANGE, NEW

JERSEY CON DENSER Application filed March 21, 1927. Serial No. 176,888.

Our invention relates to variable condensers of the plate type and is particularly designed for use in radio receiving circuits.

One of the .objects of the invention is the production of "a condenser which, while simple in structure, possesses a rigidity of blade not possible with the ordinary blade condenser of the art. This results in better tuning, particularly on the lower wave lengths Where a slight vibration of the blades of the commonly-used condensers is suflicient to alter the capacity'to a considerable degree.

Another object of the invention is to so combine the'elements of our device as to utilize the full 360 movement of the dial. In accomplishing this, we have made possible greater separation of stations on the dial and consequently simplified the matter of tuning.

Another object of the invention is the elimination of all back lash. This has been sec'ured'bythe employment, in the movement by which capacity is varied, of a spirallyfiuted shaft engaging an internally fluted split nut having spring tension.

Another object of the invention is the provision of peculiarly-shaped plate elements for both the stator and movable members which will make possible minute capacity adjustments.

Another object of the invention, where a plurality of units are employed as in tandem condensers, is the provision of adjustable compensators for the purpose of balancing the various units so that their capacities will be the same at any given point within their range, the construction of these compensators being novel and such as to adaptthem for quick and effective operation.

Further objects and advantages flowing from our novel construction, arrangement and combination of parts will be evident from the description and the accompanying drawings forming part hereof.

lVe attain the foregoing objects by a con denser wherein one series of plates which are made movable may be brought by a sliding movement, into greater or less overlapping relation with a series of plates which are stationary for the purpose of varying capac ity, this movement being secured by means of a spirally-fluted shaft attached to the knob of a dial, the whole being so combined that a full revolution of the dial is required before the limit of the path of travel of the movable plates is reached in either direction. These plates may be made either straight or V-shaped, are designed to permit wide range of variation in capacity and possess marked stability. Y Ve equip the tandem condensers described with compensators which are simple and eliicient for the purpose set forth and by means of guide rods and a stabilizing plate the condenser as a whole is made rigid and durable.

In the drawings forming part hereof,

Figure l is a perspective view of a single unit condenser embodying our invent-ion;

Fig. 2 is a plan view of the same with parts in section;

Fig. 3 is a section taken on the line 33 of Fig. 2;

Fig. 4 is a perspective view of a tandem condenser constructed in accordance with our invention;

Fig. 5 is a plan view of the same, the plates of the movable element being positioned at their outer limit of movement;

Fig. 6 shows the rear plate of the condenser shown in Fig. 4;

Fig. 7 is a section on the line 77 of Fig. 5;

Fig. 8 is a section taken on the line 88;

Fig. 9 a section on the line 99 of Fig. 7; and

Fig. 10 illustrates a section of the shaft and the means for engaging the same.

Referring to Figs. 1, 2 and 3 of the drawings, showing our improved single unit condenser, 1 indicates a. stationary base on which are mounted rigidly in any suitable Way a series of spaced plates 1, constituting a stator, and 2 a movable base carrying insulators 3 surmounted by a series of similarly rigidly mounted plates 2. One of the insulators 3 is shown in section in Fig. 2. They are threaded to receive screws 24 and 25 which attach them respectively to base 2 and plates 2. 4 is a shaft which is spirally fluted for the greater part of its length as indicated at 4'. This shaft is fixedly attached to the knob 5 of the dial and base 1 by spring collar 6, sleeve 7 and collar 8, passes through an opening in base 2 and is loosely mounted for revolution in a bearing in stabilizer plate 12. Surrounding the opening in base 2 is an internally fluted split nut 9 through which the shaft passes. The base 2 is securely fastened to this nut 9 by means of the shoulder 10 on the latter and nut 11, the said internally-fluted nut being externally threaded tor'e'ceive the nut 11. As shown, the shoulder 10 abuts against one side of base 2, and on the other side the nut 11 with its accompanying washer are tightened to hold the base and-nut in firm union. 13, 13 are guide rods which are securely fastened to base 1 and stabilizer plate 12, the bearings 14 for the same in base 2 being split as clearly shown in Fig. 1. The condenser is readily taken apart as by imscrewing the nuts 12, 12', each base, with its attached elements, being a separate and distinct section. 15 are posts for attaching the condenser to a-panel for use. The series of plates 1 and 2 are mounted on headed bolts 16, the plates being spaced from each other by washers 17 and retained on the bolts by nuts 18. These condenser plates, it will be noted, are peculiarly designed in that their engaging-or overlapping sides decline gradually from their centers and are-provided at their centers with projecting portions 19. This construction of plate increases the range of adjustability and capacity and admits of delicate-regulation. 1

In Figs. 1 to 10, our invention is shown embodied in a tandem condenser. In these figures, we have used the same reference numerals to designate parts which are practically identical withsimilar parts in the single unit condenser already described. 1 designates the stationary base and 2 the movable base. 4 is the shaft, spirally fluted at 4. It is fixedly attached to the dial-knob 5 and base 1, the knob being shown fastened to a panel 20 by posts 15. The shaft isattached to stationary base 1 by collar 6, sleeve 7 and collar 8, passes'through an opening in base 2 and is revolubly mounted in a bearing in stabilizer plate 12. An internally fluted split nut 9 surrounds the opening in base 2 for the accommodation of the shaft, and the said base is fastened to the nut 9 in the way already described; that is, by shoulder 10 and the nut 11. Guide rods 13, 13, 13 are also provided which are fastened to base 1 and the stabilizer plate. The base 2 is formed with sleeves 21 through which the guide rods pass. The removal of the nuts 12 on the stabilizer plate permits the bases with their attached parts to be separated into two sections.

The tandem condenser shown in Figs. 4 to 10 is constructed with V-shaped plates shown clearly in Fig. 8 and 9. In other respects, these plates are the same as the plates already described; that is, they have projecting portions at their centers, their edges designed for overlapping relation gradually inclining away from these portions. In the tandem condensers, these plates are mounted in the following way. The movable base 2 is formed with a series of grooves 23 in which the plates 22 are fixed. The base 1 is provided with insulators 3 and surmounting these insulators is a plate 23' grooved in the same way as base 2 to receive the od-ope'rat ing plates of that member. These insulators as shown in section in Fig. 7 are fastened by two screws one, 24, attaching it to the stationary base and the other, 25, t0 the plate 23, a space separating them.

An important feature of our invention are the compensators which are adjustable by hand. One of these is attached to each unit of the condenser. They comprise the independently lovable plates 20, hinged at 27. Each of the plates 26 has an angular portion 26, 26, which slides against base 2. Their movement is regulated by slots 28in the said base and are held in any position required by stop screws 29 moving in said slots and taking into screw threaded openings in the angular portions 26 adapted to receive them. These compensators are easily adjusted and when setto harmonize the various units remain fixed until changes in capacity call for their readjustment. 30, 30 are circuit-connecting means.

WVhile we have shownthe singleunit condenser with straight plates and the tandem condenser with V-shaped plates. this is merely for illustrative purposes. Each may be constructed with either type of plate, and combined with the other elements shown and described.

In bringing the elements of our invention into operative relation, it is important that they should be so combined and adjusted that on one complete revolution of the knob of the dial, the movable member will be caused to traverse its full path of travel, either into its position of closest relation with the stator, or to the limit of its separation therefrom. Any standard form of dial may be used.

From the foregoing, it will be evident that, when the condenser is properly connected in circuit. the rotation of the knob will revolve the shaft which will actuate the movable base and by a sliding movement carry the plates of that member either away from or into overlapping relation with the fixed or stator plates. By this means and in view of the form of the plates, very fine variations in capacity are secured, the novel means by which this sliding movement is effected. that is, the spirally fluted shaft, engaging the internally fiuted split nut with its spring tension eliminates all back lash and the split bearings for the guide rods make it certain that all wear on these rods will be compensated for. The V-type of blade shown in the tandem condenser ensures maximum rigidity and this form of blade may also be used in single unit condensers. Furthermore our condenser requires no special dial but may be used with any standard dial.

We do not limit ourselves to the exact structures shown herein as various changes and modifications may be made therein without departing from the spirit of the invention disclosed or the scope of the claims appended hereto.

hat We claim as new and desire to secure by Letters Patent is:

l. The combination in a variable condenser of a stationary base having a series of condenser plates attached thereto, a stabilizer plate, a shaft spirally fluted in part fixed to said base and mounted for revolution in a bearing in the stabilizer plate, a movable base, insulators mounted thereon and condenser plates mounted on said insulators, the fluted part of the shaft extending through an internally fluted split nut attached to the movable base and adapted to actuate the movable base in a straight line to bring its plates to a greater or less degree alternately between the plates of the sta tionary base, substantially as and for the purpose described.

2. The combination in a variable condenser of a stationary base, a movable base and a stabilizer plate, a shaft spirally fluted in part fixed to the stationary base, its fluted part extending through said movable base and seated in a bearing in the stabilizer plate, insulators mounted on the movable base and condenser plates mounted on said insulators and on the stationary base, a knob attached to.one end of the shaft and adapted on rotation to operate the movable base in a straight line toward or away from the stationary base, substantially as described.

3. The combination in a variable condenser of a stationary base and a movable base, a plurality of groups of V-shaped condenser plates attached to each of said bases, a shaft spirally fluted in part fixed to said stationary base, its spiral part extending through said movable base and adapted on rotation to actuate the movable base in a straight line and bring the plurality of groups of plates mounted thereon into cooperative relation with the plurality of groups of the plates mounted on the stationary base, substantially as described.

4. The combination in a variable condenser of a stationary base and a movable base, a plurality of groups of V-shaped plates attached to each of said bases, a shaft spirally fluted in part fixed to said stationary base, its spiral part extending through an internally fluted split nut attached to the movable base and adapted on rotation to bring the plurality of groups of plates of the movable base by a sliding movement into operative relation with the plurality of groups of plates of the ,stationaryrplates, substantially as dethe movable base, a shaft spirally fluted in.

part fixed to the stationary base and mounted in a bearing in a stabilizer plate, its spiral part extending through an internally fluted split nut attached to the movable base and adapted on rotation to bring the plurality of groups of plates of the movable base by a sliding movement into operative relation with the plurality of groups of plates of the stationary base, substantially as described.

6. The combination in a variable condenser of a stationary base and a movable base and a stabilizer plate, a shaft spirally fluted in part fixed to the stationary base, its fluted part extending through said movable base and seated for revolution in a bearing in the stabilizer plate, insulators mounted on the stationary base and a plurality of groups of V-shaped condenser plates mounted on said insulators and on the movable base, a knob attached to one end of the shaft and adapted on rotation to actuate the movable base in a straight line and bring the plurality of groups of plates on the said base into cooperative relation with the plurality of groups of plates on the stationary base, substantially as described.

7 The combination in a variable condenser of a stationary base and a movable base, a plurality of groups of V-shaped condenser plates attached to each of said bases, a compensator attached to each of said groups and adjustable by means of pin and slot connections in the movable base, a shaft spirally fluted in part fixed to the stationary base, its spiral part extending through an internally fluted split nut attached to the movable base and adapted on rotation to bring the plurality of groups of plates of the movable base by a sliding movement into operative relation with the plurality of groups of plates of the stationary base, substantially as described.

8. The combination in a variable condenser of a stationary base and a movable base, a plurality of groups of Vshaped condenser plates attached to each of said bases, a two-leafed compensator attached to the respective groups, each of said leaves being independently adjustable by means of separate pin and slot connections in one of the said bases, a shaft spirally fluted in part fixed to the stationary base, its spiral part extending through an internally fluted split nut attached to the movablebase and adapted on rotation to bring the plurality of groups of plates'of the movable base by a sliding movement into'operative relation with the plurality of groups of plates of the stationary base, substantially as described In testimony whereof, we have signed our names to this specification.

ROBERT B. MORRIS. HILMER PETERSON. 

